1. Field
One or more embodiments of the present invention relate to a hormone secretion modulator including a peptide derived from telomerase, more particularly, a peptide comprising an amino acid sequence of SEQ ID NO: 1, an amino acid sequence having a sequence identity of at least 80% with SEQ ID NO: 1, or a peptide fragment thereof, a pharmaceutical composition comprising the hormone secretion modulator, and a use of the pharmaceutical composition for treatment, alleviation, or prevention of diseases caused by excessive or deficient levels of hormones.
2. Description of the Related Art
Hormones related to generation, development, and aging of reproductive organs of humans are called sex hormones, and representative examples of the sex hormones include testosterone, estrogen, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and gonadotropin-releasing hormone (GnRH).
Testosterone is one of the primary sex hormones produced in the bodies of both males and females. Testosterone is primarily produced in interstitial cells (Leydig cells) of testicles in males and in the ovaries and placenta in females. Also, testosterone is produced in adrenal cortex in both males and females. One of the primary roles of testosterone is the development of secondary sexual characteristics, for example, increasing masses of muscles, bones, and bodily hair.
LH is a glycoprotein hormone comprised of two subunits. Alpha subunits of LH are similar to those of FSH, human chorionic gonadotropin (hCG), and thyroid-stimulating hormone (TSH). Beta subunits of LH are different from those of other glycoprotein hormones and provide biochemical specificity to LH. LH is secreted from anterior pituitary, and in males, LH is secreted after reacting with GnRH secreted from hypothalamus. LH is also known as interstitial-cell-stimulating hormone (ICSH) and the secretion of LH is regulated by a balance of positive and negative feedback mechanisms including a hypothalamic-pituitary axis, reproductive organs, a pituitary gland, and sexual steroid hormones. LH and the other pituitary gonadotropin and FSH, play a critical role in maintaining the normal function of the male and female reproductive systems.
FSH is a glycoprotein hormone comprised of two subunits. Alpha subunits of FSH are similar to those of LH, hCG, and TSH. Beta subunits of FSH are different from those of other glycoprotein hormones and confer biochemical specificity. FSH is secreted from anterior pituitary in response to GnRH secreted from hypothalamus. In both males and females, FSH secretion is regulated by a balance of positive and negative feedback mechanisms involving the hypothalamicpituitary axis, the reproductive organs, and the pituitary and sex steroid hormones. FSH and LH and the other pituitary gonadotropin play a critical role in maintaining the normal function of the male and female reproductive systems.
Estrogen is a female steroid hormone, which is mostly produced in the ovaries, and a small amount of estrogen is produced in adrenal cortex, placenta, and male testes. Estrogen helps control and guide sexual growth including physical changes associated with puberty. It also influences the course of ovulation in the monthly menstrual cycle, lactation after pregnancy, aspects of mood, and the aging process. Production of estrogen changes naturally over the female lifespan, reaching adult levels with the onset of puberty (menarche) and decreasing in middle age until the onset of menopause. Estrogen deficiency can lead to lack of menstruation (amenorrhea), persistent difficulties associated with menopause (such as mood swings and vaginal dryness), and osteoporosis in older age. In cases of estrogen deficiency, natural and synthetic estrogen preparations may be prescribed. Estrogen is also a component of many oral contraceptives. An overabundance of estrogen in men causes development of female secondary sexual characteristics (feminization), such as enlargement of breast tissue.
The gonadotropin-releasing hormones (GnRH) (gonadoliberin) are a family of peptides that play a pivotal role in reproduction. The main function of GnRH is to act on the pituitary to stimulate the synthesis and secretion of luteinizing and follicle-stimulating hormones, but GnRH also acts on the brain, retina, sympathetic nervous system, gonads, and placenta in certain species. There seems to be at least three forms of GnRH. The second form is expressed in midbrain and seems to be widespread. The third form has been found so far only in fish. GnRH is a C-terminal amidated decapeptide processed from a larger precursor protein. Four of the ten residues are perfectly conserved in all species where GnRH has been sequenced.